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991.
992.
Expression of Mx protein and interferon-alpha (IFN-alpha) was examined by immunohistochemistry in pigs experimentally infected with swine influenza virus. In infected pigs euthanatized at 1 day postinoculation (dpi), the lumen of bronchioles were filled with large numbers of mononuclear cells, small numbers of neutrophils, sloughing epithelial cells, and proteinaceous fluid. Lesions at 3 and 5 dpi were similar but less severe. Alveolar spaces were filled with neutrophils. By 7 and 10 dpi, microscopic lesions were resolved. The immunohistochemical signals for Mx protein and IFN-alpha antigen were confined to cells in areas that had hybridization signal for swine influenza virus. In situ hybridization and immunohistochemistry of serial sections of lung indicated that areas containing numerous swine influenza virus RNA-positive cells also have numerous Mx and IFN-alpha antigen-positive cells. Mean immunohistochemical scores for Mx protein-positive cells were correlated with mean immunohistochemical scores for IFN-alpha antigen-positive cells (r(s) = 0.8799, P < 0.05). These results indicated that Mx protein and IFN-alpha antigen were expressed in the lung from pigs experimentally infected with swine influenza virus, but their biological functions remain to be examined.  相似文献   
993.
Few studies regarding the anatomical distribution of motor neurons innervating muscles of the arm have been demonstrated in avian brains. The purpose of this study was to finely determine the localization of cerebral neurons innervating the biceps brachii muscle in the pigeon. The cholera toxin B subunit (CTB) was employed as a retrograde tracer to determine the location of neurons controlling the biceps brachii muscle in the telencephalon following intramuscular injection in male pigeons (= 7), which were killed 14 days after intramuscular injection with CTB. We found that CTB‐labelled neurons were located contralaterally in the hyperpallium apicale of the rostral telencephalon and that most of the CTB‐labelled neurons were pyramidal in shape. This study shows that CTB is easily taken up by nerve terminals which innervate the biceps brachii muscle of the pigeon and that cerebral motor neurons controlling the biceps brachii muscle are located in the hyperpallium apicale.  相似文献   
994.
The plasma source ion implantation (PSII) technique was used to improve the adhesion between linear low-density polyethylene (LLDPE) and biopolymer. LLDPE was treated with the PSII using O(2) or CF(4) gas to modify its surface. After modification, chitosan or corn zein was used for coating on LLDPE. Wettability of the LLDPE surface was evaluated with a contact angle meter by the sessile drop method. X-ray photoelectron spectroscopy (XPS) was used to analyze the LLDPE surface. Before and after treatment, in the case of LLDPE treated with O(2) PSII, oxygen-containing functional groups were formed on the implanted surface. In the CF(4) PSII treated LLDPE, it was observed that the fluorine concentration on the surface of LLDPE remarkably increased and hydrophobic groups were formed by chemical reaction. Bilayer films coated with chitosan or corn zein showed 10 times lower oxygen permeability. Tensile strength of multilayer films was decreased a little compared with that of LLDPE. The plastic and biopolymer multilayer films have potential for food packaging application because of their O(2) gas barrier property and easy recyclability of the multilayer film.  相似文献   
995.
Cholinesterases are key enzymes that play important roles in cholinergic transmission. Nine flavonoids displaying cholinesterase inhibitory activity were isolated from the root bark of Morus lhou L., a cultivated edible plant. The isolated compounds were identified as a new flavone (1), 5'-geranyl-5,7,2',4'-tetrahydroxyflavone (2), kuwanon U (3), kuwanon E (4), morusin (5), morusinol (6), cyclomorusin (7), neocyclomorusin (8), and kuwanon C (9). All compounds apart from compound 6 inhibited cholinesterase enzyme in a dose-dependent manner with K(i) values ranging between 3.1 and 37.5 μM and between 1.7 and 19.1 μM against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes, respectively. The new compound was charactierized as 5'-geranyl-4'-methoxy-5,7,2'-trihydroxyflavone (1). It showed the most potent inhibitory activity (K(i) = 3.1 μM for AChE, K(i) = 1.74 μM for BChE). Lineweaver-Burk and Dixon plots and their secondary replots indicated that flavones (5-9) with prenyl substitution on C-3 were noncompetitive inhibitors, whereas those unsubstituted (1-4) at C-3 were mixed inhibitors of both AChE and BChE. In conclusion, this is the first study to demonstrate that alkylated flavonoids of M. lhou have potent inhibitory activities against AChE and BChE.  相似文献   
996.
Fusarium head blight (FHB) caused by Fusarium graminearum is one of the most destructive fungal diseases. Wide spread of FHB causes yield loss, quality reduction, and accumulation of poisonous mycotoxins. Twenty-three Korean wheat cultivars and a known FHB resistant cultivar ‘Sumai 3’ were tested for Type I and Type II resistance to FHB and evaluated for grain characteristics. Wheat cultivars showed infection scores of 0.6 (the lowest) to 7.8 (the highest) in response to the Fusarium inoculation for Type I evaluation. Three Korean cultivars, ‘Chungkye’ (1.8), ‘Tapdong’ (1.8), and ‘Jinpoom’ (1.6) showed relatively good FHB resistance compared to ‘Sumai 3’ (0.6) for Type I evaluation. On the other hand, Type II evaluation scores ranged between 1.4 and 3.6. The infection scores of ‘Uri’ (1.4) and ‘Jinpoom’ (1.4) were particularly low and even lower than “Sumai 3” (1.6). The relationship between grain properties and FHB severity was evaluated. Grain length was positively correlated with Type II evaluation. Spike length and total polyphenol content were negatively correlated with FHB severity of Type I evaluation. Grain properties were negatively or positively correlated with FHB severity. The obtained results indicated that some of the grain parameters could be employed in the development of wheat lines with improved FHB resistance.  相似文献   
997.
Nam SW  Chung HS  Lo YC  Qi L  Li J  Lu Y  Johnson AT  Jung Y  Nukala P  Agarwal R 《Science (New York, N.Y.)》2012,336(6088):1561-1566
Phase-change materials undergo rapid and reversible crystalline-to-amorphous structural transformation and are being used for nonvolatile memory devices. However, the transformation mechanism remains poorly understood. We have studied the effect of electrical pulses on the crystalline-to-amorphous phase change in a single-crystalline Ge(2)Sb(2)Te(5) (GST) nanowire memory device by in situ transmission electron microscopy. We show that electrical pulses produce dislocations in crystalline GST, which become mobile and glide in the direction of hole-carrier motion. The continuous increase in the density of dislocations moving unidirectionally in the material leads to dislocation jamming, which eventually induces the crystalline-to-amorphous phase change with a sharp interface spanning the entire nanowire cross section. The dislocation-templated amorphization explains the large on/off resistance ratio of the device.  相似文献   
998.
Pulse starches were isolated from different cultivars of pea, lentil, and chickpea grown in Canada under identical environmental conditions. The in vitro digestibility and physicochemical properties were investigated and the correlations between the physicochemical properties and starch digestibility were determined. Pulse starch granules were irregularly shaped, ranging from oval to round. The amylose content was 34.9–39.0%. The amount of short A chains (DP 6‐12) of chickpea starch was much higher than the other pulse starches, but the proportions of B1 and B2 chains (DP 13‐24 and DP 25‐36, respectively) were lower. The X‐ray pattern of all starches was of the C type. The relative crystallinity of lentil (26.2–28.3%) was higher than that of pea (24.4–25.5%) and chickpea starches (23.0–24.8%). The swelling factor (SF) in the temperature range 60–90°C followed the order of lentil ≈ chickpea > pea. The extent of amylose leaching (AML) at 60°C followed the order of pea ≈ chickpea > lentil. However, in the temperature range 70–90°C, AML followed the order of lentil > pea > chickpea. The gelatinization temperatures followed the order of lentil > pea > chickpea. The peak viscosity, setback, and final viscosity of pea starch were lower than those of the other starches. Lentil starch exhibited lower rapidly digestible starch (RDS) content, hydrolysis rate, and expected glycemic index (eGI). The resistant starch (RS) content of both lentil cultivars was nearly similar. However, pea and chickpea cultivars exhibited wide variations in their RS content. Digestibility of the pulse starches were significantly correlated (P < 0.05) with swelling factor (60°C), amylose leaching (60°C), gelatinization temperature, gelatinization enthalpy, relative crystallinity, and chain length distribution of amylopectin (A, B1, and B2 chains).  相似文献   
999.
The in vitro starch digestion rate and estimated glycemic index (GI) of oat flours and oat starches from typical and high β-glucan oat lines were evaluated along with the impact of heating on starch digestion. Flour from oat lines ('Jim', 'Paul', IA95, and N979 containing 4.0, 5.3, 7.4, and 7.7% β-glucan, respectively) was digested by pepsin and porcine pancreatin. To determine the impact of heating on starch digestion, oat slurries were prepared by mixing oat flour and water (1:8 ratio) and heating for 10 min prior to digestion. Viscosity, as measured on a Rapid Visco Analyzer, increased with increases in concentration and molecular weight of β-glucan. The in vitro starch digestion of oat flours and a control, white bread made from wheat flour, increased as the digestion time increased. Starch digestion of oat flour was slower than that of the control (p < 0.05). Heat treatment of oat-flour slurries increased the starch digestion from a range of 31-39% to a range of 52-64% measured after 180 min of in vitro digestion. There were no differences in starch digestibility among oat starches extracted from the different oat lines. The GI, estimated by starch hydrolysis of oat flours, ranged from 61 to 67, which increased to a range of 77-86 after heating. Oat-flour slurries prepared from IA95 and N979 lines with high β-glucan concentrations had lower GI values than did slurries made from Jim and Paul lines. Starch digestion was negatively correlated with β-glucan concentrations in heated oat-flour slurries (R(2) = 0.92). These results illustrate that the oat soluble fiber, β-glucan, slowed the rate of starch digestion. This finding will help to develop new food products with low GI by using oat β-glucan.  相似文献   
1000.
Ultraviolet (UV) radiation can cause inflammatory changes and may further contribute to skin carcinogenesis. Anthocyanins are known to be powerful antioxidants that help protect plants from UV damage. Recently, we isolated anthocyanins from black soybean [Glycine max (L.) Merr] seed coats. Thus, we investigated the protective effect of anthocyanins from black soybean seed coats on UVB radiation-induced inflammatory responses and the molecular mechanism responsible for regulation of apoptosis and inflammatory responses. Anthocyanins inhibited UVB-induced cylooxygenase-2 (COX-2) and PGE 2 production through a nuclear factor-kappaB-dependent pathway and regulation of the PI3 kinase/Akt pathway activated by UVB in a human keratinocyte cell line, HaCaT. Topical application of anthocyanins prior to UVB irradiation of hairless mice also inhibited induction of COX-2 and PGE 2. In conclusion, it is suggested that anthocyanins from the seed coat of black soybeans can be used as a useful drug to modulate oxidative disorders including UVB-induced inflammation.  相似文献   
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